Accession Number : AD0726346

Title :   Certain Peculiarities of the Raman Spectra of Adsorbed Molecules,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Pershina,E. V. ; Raskin,Sh. Sh.

Report Date : 10 JUL 1971

Pagination or Media Count : 18

Abstract : In view of the fact that Raman spectra of compounds adsorbed on surfaces of glass, silica gel, and alumosilica gel has not been studied before, and in view of the additional information that Raman spectra can yield on the vibrational spectra of the adsorbed molecules, the authors used a technique to measure the spectra of sublimated and adsorbed films of SbCl3, SbBr3, 1,2-dichloroethane, benzene, naphthalene, diphenyl, para-terphenyl, acetophenone, acetonitryl, nitromethane, and others. The spectra revealed deviations from those of the condensed phase at room temperature. The deviations are classified into three groups: Some with very slight deviations (benzene, naphthalene, 1,2,4,5-tetrachlorobenzene), showing that rigid molecules are not strongly affected by adsorption; Substances containing CO or CN groups, with larger frequency shifts of individual lines; Compounds (SbCl3, SbBr3, dichloroethane, etc.) whose entire spectrum is noticeably altered, and for which it is proposed that adsorption changes the isomeric composition. The effect of the thickness of the adsorbed layer on the result is discussed. The results are compared with other published data and explanations for differences are proposed. (Author)

Descriptors :   (*RAMAN SPECTROSCOPY, *ADSORPTION), (*INFRARED SPECTRA, ORGANIC COMPOUNDS), GLASS, SILICON DIOXIDE, FILMS, ANTIMONY COMPOUNDS, CHLORIDES, BROMIDES, HALOGENATED HYDROCARBONS, BENZENE, NAPHTHALENES, BIPHENYL, ACETOPHENONES, ACETONITRILE, USSR

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE